package com.harbour.mmall.service.impl;



import com.google.common.collect.Lists;
import com.google.common.collect.Sets;
import com.harbour.mmall.common.ServerResponse;
import com.harbour.mmall.dao.CategoryMapper;
import com.harbour.mmall.pojo.Category;
import com.harbour.mmall.service.ICategoryService;
import org.apache.commons.lang.StringUtils;
import org.slf4j.Logger;
import org.slf4j.LoggerFactory;
import org.springframework.beans.factory.annotation.Autowired;
import org.springframework.stereotype.Service;
import org.springframework.util.CollectionUtils;

import java.util.List;
import java.util.Set;


@Service("iCategoryService")
public class CategoryServiceImpl implements ICategoryService {

    private Logger logger = LoggerFactory.getLogger(CategoryServiceImpl.class);


    @Autowired
    private CategoryMapper categoryMapper;


    public ServerResponse addCategory(String categoryName,Integer parentId){
         if(parentId == null || StringUtils.isBlank(categoryName)){
             return ServerResponse.createByErrorMessage("添加品类参数错误");
         }
         Category category = new Category();
         category.setName(categoryName);
         category.setParentId(parentId);
         category.setStatus(true);
         int rowCount = categoryMapper.insert(category);
         if(rowCount>0){
             return ServerResponse.createBySuccessMessage("添加品类成功");
         }
         return ServerResponse.createByErrorMessage("添加品类失败");
    }

    public ServerResponse updateCategoryName(Integer categoryId,String categoryName){
        if(categoryId == null || StringUtils.isBlank(categoryName)){
            return ServerResponse.createByErrorMessage("更新品类参数错误");
        }
        Category category = new Category();
        category.setId(categoryId);
        category.setName(categoryName);
        int rowCount = categoryMapper.updateByPrimaryKeySelective(category);//有选择性更新
        if(rowCount>0){
            return ServerResponse.createBySuccessMessage("更新品类成功");
        }
        return ServerResponse.createByErrorMessage("更新品类失败");
    }


    public ServerResponse<List<Category>> getChildrenParallelCategory(Integer categoryId){
        List<Category> categoryList = categoryMapper.selectCategoryChildrenByParentId(categoryId);
        if(CollectionUtils.isEmpty(categoryList)){  //判断categoryList里面是否为空
            logger.info("未找到当前分类的子分类");
        }
        return  ServerResponse.createBySuccess(categoryList);
    }

    //递归查询本节点的id及孩子节点的id
    public ServerResponse<List<Integer>> selectCategoryAndChildrenById(Integer categoryId){
        Set<Category> categorySet = Sets.newHashSet();
        findChildCategory(categorySet,categoryId);//递归操作

        List<Integer> categoryIdList = Lists.newArrayList();
        if(categoryId != null){
            for(Category categoryItem : categorySet){
                categoryIdList.add(categoryItem.getId());
            }
        }
        return ServerResponse.createBySuccess(categoryIdList);
    }

    private Set<Category> findChildCategory(Set<Category> categorySet,Integer categoryId){
        Category category = categoryMapper.selectByPrimaryKey(categoryId);
        if(category != null){
            categorySet.add(category);
        }
        //查找子节点，递归算法一定要有退出条件
        List<Category> categoryList = categoryMapper.selectCategoryChildrenByParentId(categoryId);//mybatis如果没查到数据是不会返回null对象
        for(Category categoryItem : categoryList){
            findChildCategory(categorySet,categoryItem.getId());
        }
        return  categorySet;
    }




}
